Description

The HKS Mastery ECU is a comprehensive, multi-stage reflash service that unlocks the hidden potential of your GR86/BRZ’s FA24 engine. Unlike generic tuning files, each “Phase” is a precise, vehicle-specific calibration developed by HKS engineers through extensive real-world and dyno testing. By sending your factory ECU to HKS, you receive a professionally optimized tune that enhances drivability, responsiveness, and power, tailored to your vehicle’s modification level—from stock to supercharged.

Product Overview 

This service replaces the stock ECU’s conservative factory programming with HKS’s proprietary performance calibrations. It is a reliable, plug-and-play solution that requires no additional hardware or complex installation, offering a significant upgrade in driving feel and performance. The service is structured in progressive phases to match your vehicle’s setup:

• Phase 1 (Code 42019-AT026): The foundational tune. Removes the 180 km/h speed limiter, offers optional cooling fan and cold start idle adjustments, and improves overall drivability. Does not target peak power gains.

• Phase 2 (Code 42019-AT027): The performance NA tune. Optimizes ignition timing, fuel maps, and valve timing to fill in the “torque valley,” increase high-RPM pull, and deliver smoother, stronger power throughout the rev range. Selectable for stock or HKS GT-Spec exhaust manifolds.

• Phase 3 (S/C) (Code 42019-AT028): The dedicated supercharger tune. Exclusively for use with the HKS GT2 Supercharger Pro Kit (12001-AT013). Unlocks the full potential of the supercharger with optimized boost, fueling, and timing maps for massive, reliable gains.

Product Highlights

🔧 Engineered by HKS, Tested on Real Cars
Every Mastery ECU calibration is the product of rigorous development on actual GR86/BRZ vehicles at HKS facilities. This ensures real-world reliability, seamless drivability, and performance that you can feel on the road or track, not just on a dyno chart.

📈 Progressive, Application-Specific Tuning
The phased approach allows you to select the exact level of performance that matches your modifications. From a refined daily driver (Phase 1) to a fully optimized supercharged build (Phase 3), there is a calibrated solution.

⚙️ Enhanced Drivability & Refinement
Beyond peak numbers, HKS tuning focuses on the driving experience. Phase 2 specifically targets the elimination of the stock mid-range torque dip, resulting in a linear, responsive powerband that embodies the best characteristics of a naturally aspirated engine.

🛡️ Safety & Reliability First
These are conservative, durability-focused tunes designed for the street. They work in harmony with the factory’s robust safety protocols and diagnostic systems, providing peace of mind alongside increased performance.

Technical Specifications

• Product Name: Mastery ECU (ECU Reflash Service)

• Model Codes & Applications:

  • Phase 1: 42019-AT026 – Speed limiter removal, drivability refinements.

  • Phase 2: 42019-AT027 – Performance NA tune for bolt-on mods. (+~5 PS, optimized torque curve).

  • Phase 3 (S/C): 42019-AT028 – Dedicated tune for HKS GT2 Supercharger Kit. (+~66 PS, +~9.7 kgf·m).

• Process: Mail-in service. ECU is returned within 3 business days of receipt at HKS.

• Free Options: Lower electric fan activation temp (-3°C) and cold start idle correction.

• Requirements: Manual Transmission (MT). Must remove aftermarket throttle controllers for Phase 2 & 3.

Performance Philosophy

• Goal: To deliver a factory-like refinement with enhanced performance by fully optimizing the engine’s control parameters within safe limits. The focus is on real-world driveability, throttle response, and a linear power delivery that makes the car more enjoyable at every RPM.

• Focus: A trusted, hassle-free tuning solution. It is the ideal choice for owners who want professional results without the complexity of stand-alone ECUs or the risks of untested “off-the-shelf” tune files. It represents HKS’s complete engine tuning philosophy in a direct, applicable service.

Service & Usage Notes

• 📮 Simple Mail-In Process

  1. Remove and ship your ECU to HKS in the provided packaging.

  2. HKS reprograms and tests the ECU with your selected Phase.

  3. ECU is shipped back within 3 business days for reinstallation.
     Vehicle downtime is typically less than one week.

• ⚠️ Critical Compatibility & Recommendations

  • Phase 3 (S/C) is mandatory for the GT2 Supercharger Kit and requires the specific Φ43mm restrictor supplied with the ECU.

  • For Phase 3, HKS strongly recommends simultaneous installation of the Super Manifold GT Spec (33005-AT010) to protect the factory catalytic converter.

  • Phases 2 & 3 are not compatible with aftermarket electronic throttle controllers.